Love the watercolor one =)
I'm not a fan of the "manikin" method some art schools use, it makes the figures look stiff and you're not really learning how to draw organically. I only use it for some extreme foreshortening because it can be useful in that case.
I think you should try to draw figures with as few lines as possible, try to get the force lines with just one gesture, follow the curves of the body with one line. You did it with the 7 min. one (well, most of it) and in fact it looks better and more natural. Maybe lower the time, make it like 3 minutes, that will force you to become faster and more confident in tracing the body with only one line.
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